Selective herbicidal composition



Patented Jan. 20, 1953 UNITED STATE s PATENT QFFICE SELECTIVE H ERIBICIDA'L GOMPO'SITIGN' Frank J; Sowa, .Cranford', ,N.",J;'

No Drawing. Application February 8", I952; SerialNo. 270,749

As' described in my co-pending application,

Serial No. 136-, 850'filed January 4, 1950, as filed, it has been found that ammonia-boron fluoride compounds such as monoammino boron trifiuoride (NH3.BF3) and; ammonium fiuoborate (NH4BF4) may be used for weed killing and sterilizing soil although'they also may be. used for the selective killing of crabgrass when they areused in combination with a. wetting agent and are appliedin limited concentrations. Itv is also well known that chlorinated phenoxy acetic acids, such as. 2,4:dichloro phenoxy acetic acid and, 2,4,57'131'1011101'0. phenoxy. acetic acid and the salts and esters. of these acids (commonly known as 2,4-D and 2,4,.5-T) are usefulin.kill'ing broad leaf plants such as plantain.

2A-,-D and 2,4,5-T have limitations as herbicidal compositions in that they are not active in killing crabgrass which has matured beyond the single lea-f stage. On the other hand the ammoniaboron fluoride compounds generally have to' be employed in relatively high concentrations even when a wetting agent is used in order to be effective in killing crab grass.

I have now discovered thatthese two-types of weed-killing agents, when employed in combina,-: tion; are effectivefor"the selective-kiiling of crab grass atsurprisingly-"reducedconcentrations. Furthermore; thetendency for" the" compositionto. injurethe desired grasses is :much more limited atthe. concentrations required for effective kill..- ing of crab grass when these two agents. are. used in. combination.

Qne of the objectsof the. present invention is-to provide a novelweedrkilling composition.

Another objectiof the. invention is to .kill crabgrass and broad leaf :plants without substantial injury toother more desirable grasses.

Alfurther object of. the: invention is to reduce the amount of herbicidal agent required for crab grass control.

These and other objects and featuresof the present invention will appear from the following description thereof in which typical compositions and methods are described for the. purpose of indicating the nature of the present invention but without intending to limit the scope of the invention thereby.

Thecompositions of the present invention contain, as their essential active ingredients, an ammonia-boron, fluoridetcomposition and a, polychlorinated 'phenoxy acetic acid compound. The ammonia-boron fluoride compound may be monoammino boron. trifluoride, (NHaBFs) or ammonium fluoborate; (NI-hBFr), whereas: the.

22' phenoxy acetic acid compoundmay be selected from the, ammonium; and amine salts and the.

esters-of either 2,4-dichlorophenoxy acetic-acid. (hereinreferred to as 2,4-D) or 2,4,5r trichloro phenox-y acetic: acid. herein referred. to. as 2,4;5-T).. The ammonium salts of each aciclare preferred although the amine salts of, the acids, such as. thepropyl, butyl, octyl-,.laury-l-, dimethyl; trimethyl, ethyl, diethyL, triethyl, triethanol,

r isopropanol, allyl and abietyl ami-ne. salts may be.

used. lt isalso found that. esters of thechloro phenoxy acetic, acids such as the. normalpropyl,

isopropyl, normal butyl, isobutyl, amyl andsoctyl esters as well as the esters of monoethyl ether of ethylene glycol or diethyleneglycol are very effectives the. surfaces. to-which. they are; applied.

if effective.coverage-and killingwaction is;to re-- sult.. In fact, it may well be; thatthe: spreading agent has some. activating or synergistic. effect inthe combinations,v

The preferred :forms of. wetting; agent. :used: are.

those of the. non-ionic type such aspolyethylene: etherof fatty alcohols. or polyethylene-glycol con.- densation products-or; in fact, substantially any of. the. conventionaLwetti-ng agents. w-hichare,

compatible with. they ammoniarboron.v fluorider compounds. and},the..-cl'iloro. phenoxy acetic. acid salts... The amountlof'fthe wetting agent used.

preferably is sufficientt'o impart to .the solution ofithe active ingredients a surfacetension below about 40'dynes .per centimeter at'23 CI, although solutionsjhaving a.surface' tension up. to 50 dynes per centimeter may be. used. The amount of wetting agentemployed generally equals from .110 to 5% byweight of'the aqueous, solutionemployed in treating crab grass.

The totalamount'of "active ingredients applied" may'varyfrom' about 4'to- 50 poundsper' acre and generally isinthe neighborhood of 15 to' 35" pounds'per acre. The proportions of the ingredients are as follows:

Parts by weight Ammonia-boron,- fluoride. compound 1 to 50 Chloro phenoxyacetic acid.compound 1 to30.

Water, sufii'cient for convenientapplication.withthe equipmentavailable. Wetting agent, sufiicientto reduce. the surface tension below 50dynes per centimeter at 23 C.generally from 1 to 50 parts by weight.

The active ingredientsv are preferablymixed together and the wetting agentv distributed throughout the-mix. When the wetting agent itself'a powdered, waxyaor flaky :materi'alsuch: asi. theifi'akyi ethylene glycol; condensation product sold under the trade name Pluronics F-GS produced by Wyandotte Chemicals Corp. or the waxy form of condensation product sold under the trade.

name Emulphor ON produced by General Dyestuff Corporation (U. S. Patent 1,970,578), the resulting mixture is a substantially dry powdered product which is readily packaged for shipment and storage. When the wetting agent is a liquid form of ethylene glycol condensation product such as the product sold under the trade name Igepal 300 produced by General Dyestuff Corporation, the mixture may be in liquid form.

When using either form of mixture it is dissolved in water suificient to permit ready application by means of conventional spraying equipment and in general from 200 to 400 gallons of water having the active ingredients dissolved therein are applied to each acre to be treated. The concentration of the active ingredients in solution may vary from about 0.1 to 2% and preferably is about 1% based on the weight of the water. The composition may be applied in a single dosage although in some instances it is preferable to use more dilute olutions and to make two or three applications.

A typical and preferred composition produced in accordance with the present invention is as follows:

Example I 1 pound of NHs-BFz, 5 pounds of the ammonium salt of 2,4-D and 8 pounds of a wetting agent in the form of a polyethylene glycol condensation product (Igepal 300") are dissolved in 360 gallons of water. In tests conducted by New Jersey Agricultural Experiment Station at Rutgers University this composition was applied by conventional spraying means at the rate of 360 gallons per acre. The area treated was turf infected with crab grass. In these tests the composition described was found to be highly effective in selectively killing the crab grass in that over 90% of the crab grass was killed without appreciable or permanent injury to the remaining desired grasses. During the latter part of the summer and when the crab grass is tough and flourishing, two or three applications of the fore- I going composition may be'employed. The total amount of active herbicidal agent used was only 6 pounds per acre for a single application. Best results were obtained by making three applications one week apart whereby a total of 18 pounds per acre when 93% control was obtained.

This example provides a striking contrast with methods described in the above identified copending application since in accordance with said application, in similar tests in which the ammonia boron fluoride compound is used in combination with a wetting agent but in the absence of any chloro phenoxy acetic acid compound, it was found necessary to use 25 pounds of the active ingredients in each application or a total of 75 pounds per acre in three applications to produce comparable results. The example is further noteworthy in that the salts of 2,4-D which predominate in the mixture are not active crab grass killers when applied by themselves to mature crab grass.

The composition of Example I was employed with similar results using the ester of monoethyl ether of ethylene glycol as the ester of 2,4-D and when using the trimethyl amine salts of 2,4-D

in place of the ammonium salt of 2,4-D, the same quantities and methods of application being used.

4 Example II The composition of Example I was employed with similar results whensubstituting ammonium fiuoborate (NH4BF4) forthe monoammino boron trifiuoride (NHs-BFs).

Example III In further tests conducted at Rutgers University, 32 pounds of NHa-BFs and 1.7 pounds of ammonium salt of 2,4-D together with sufficint wetting agent to produce solutions having surface tensions of about 40 dynes per centimeter at 23 C. were dissolved in 250 gallons of water. This composition was sprayed on turf infected with crab grass at the rate of 250 gallons per acre. The composition was found to kill over of the crab grass without material or permanent injury to the other desirable grasses. The same total amount of active ingredients may be applied in two separate applications using 16 pounds of NHs-BFz and 0.85 pound of the ammonium salts of 2,4-D in 200 gallons of water per acre for each application.

Example -I V Pounds NH3.BF3 30 2,4-D (ammonium salt) 150 Wetting agent 240 A mixture of the type used in forming the solution H of Example III is as follows:

Pounds NI-I3.BF3 '0 2,4-D (ammonium salt) 50 Wetting agent dition of other agents thereto and by their application in other Ways to areas in which weeds or vegetation is to be killed. In view thereof it should be understood that the examples cited above are intended to be illustrative only and are not intended to limit the scope of the invention.

I claim: 1. An herbicidal composition comprising as active ingredients from 1 to 50 parts by weight of an ammonia-boron fluoride compound selected from the group consisting of monoammino boron trifluoride and ammonium fluoborate and from 1 to 30 parts by weight of a chloro phenoxy acetic acid compound selected from the group consisting of the ammonium and amine salts and the esters of 2,4-dichloro phenoxy acetic acid and 2,4,5-trichloro phenoxy acetic acid together with a wetting agent which is compatible in aqueous solution with said ingredients.

2. An herbicidal composition comprising as ac- VI two ingredients 1 to 50 parts by weight of an No separation or deterioration of the While various compositions have been decribed and typical methods for using such com-- positions have been cited it will be apparent that they may be varied considerably by the adammonia-boron fluoride compound selected from the group consisting of monoammino boron trifluoride and ammonium fluoborate and from 1 to parts by weight of a chloro phenoxy acetic acid compound selected from the group consisting of the ammonium and amine salts and the esters of 2,4-dichloro phenoxy acetic acid and 2,4,5-trichloro phenoxy acetic acid to ether with from 1 to 50 parts by weight of a non-ionic Wetting agent.

3. An herbicidal composition containing approximately 1 part by weight of an ammoniaboron fluoride compound selected from the group consisting of monoammino boron trifluoride and ammonium fluoborate, 5 parts by weight of a compound selected from the group consisting of the ammonium and amine salts and the esters of 2,4-dichloro phenoxy acetic acid and 2,4,5-trichloro phenoxy acetic acid, and 8 parts by weight of a non-ionic wetting agent.

4. An herbicidal composition containing approximately 950 parts by weight of an ammoniaboron fluoride compound selected from the group consisting of monoammino boron trifluoride and ammonium fluoborate, 50 parts by weight of a compound selected from the group consisting of the ammonium and amine salts and the esters of 2,4-dichloro phenoxy acetic acid and 2,4,5-trichloro phenoxy acetic acid, and 30 parts by weight of a non-ionic wetting agent.

5. An herbicidal composition consisting of an aqueous solution containing from about 0.10 to 2% by weight of active ingredients comprising an ammonia-boron fluoride compound selected from the group consisting of monoammino boron trifluoride and ammonium fluoborate, and a compound selected from the group consisting of the ammonium and amine salts and the esters of 2,4-dichloro phenoxy acetic acid and 2,4,5-trichloro phenoxy acetic acid, said composition containing a non-ionic Wetting agent and having a surface tension below 50 dynes per centimeter at 23 C.

6. An herbicidal composition consisting of an aqueous solution containing from about 0.10 to 2% by weight of active ingredients comprising an ammonia-boron fluoride compound selected from the group consisting of monoammino boron trifluoride and ammonium fluoborate, and a compound selected from the group consisting of the ammonium and amine salts and the esters of 2,4-dichloro phenoxy acetic acid and 2,4,5-trichloro phenoxy acetic acid, and from 0.10 to 5% by Weight of a non-ionic wetting agent.

'7. An herbicidal composition consisting of an aqueous solution containing from about 0.10 to 2% by weight of active ingredients of which from 1 to 50 parts by weight is an ammonia-boron fluoride compound selected from the group consisting of monoammino boron trifluoride and ammonium fluoborate, and from 1 to 30 parts by weight is a chloro phenoxy acetic acid compound selected from the group consisting of the ammonium and amine salts and the esters of 2,4- dichloro phenoxy acetic acid and 2,4,5-trichloro phenoxy acetic acid, said solution containing a non-ionic wetting agent and having a surface tension below 50 dynes per centimeter at 23 C.

8. An herbicidal composition consisting of an aqueous solution containing from about 0.10 to 2% by weight of active ingredients of which 1 part by weight is an ammonia-boron fluoride compound selected from the group consisting of monoammino boron trifluoride and ammonium fluoborate, and 5 parts by weight is a chloro phenoxy acetic acid compound selected from the group consisting of the ammonium and amine salts and the esters of 2,4-dichloro phenoxy acetic acid and 2,4,5-trichloro phenoxy acetic acid, said solution containing a non-ionic wetting agent and having a surface tension below 50 dynes per centimeter at 23 C.

9. An herbicidal composition consisting of an aqeuous solution containing from about 0.10 to 2% by weight of active ingredients of which parts by weight is an ammonia-boron fluoride compound selected from the group consisting of monoammino boron trifluoride and ammonium fluoborate, and 5 parts by weight is a chloro phenoxy acetic acid compound selected from the group consisting of the ammonium and amine salts and the esters of 2,4-dichloro phenoxy acetic acid and 2,4,5-trichloro phenoxy acetic acid, said solution containing a non-ionic wetting agent and having a surface tension below 50 dynes per centimeter at 23 C.

10. The method of selectively killing crab grass which comprises the steps of applying thereto an aqueous solution containing from 0.10 to 2% of a mixture of active ingredients consisting of an ammonia-boron fluoride compound selected from the group consisting of monoammino boron trifluoride and ammonium fluoborate and a chloro phenoxy acetic acid compound selected from the group consisting of the ammonium and amine salts and the esters of 2,4-dichloro phenoxy acetic acid and 2,4,5-trichloro phenoxy acetic acid, said solution containing a wetting agent and having a surface tension below about 50 dynes per centimeter at 23 0., the rate of application of said solution being such as to apply from about 5 to 50 pounds of said active ingredients to an acre of turf to be treated.

11. The method of selectively killing crab grass which comprises the steps of applying an aqueous solution containing as active ingredients monoammino boron trifluoride and the ammonium salt of 2,4-dichloro phenoxy acetic acid to the crab grass at the rate of from about 5 to 50 pounds of active ingredients per acre, said solution containing a wetting agent and having a surface tension below 50 dynes per centimeter at 23 C.

12. The method of selectively killing crab grass which comprises the steps of applying to the crab grass a solution containing 1 pound of monoammino boron trifluoride and 5 pounds of the ammonium salt of 2,4-dichloro phenoxy acetic acid together with a wetting agent dissolved. in from 200 to 400 gallons of water, the solution being applied at the rate of from about 6 to 18 pounds of active ingredients per acre, said solution having a surface tension below 50 dynes per centimeter at 23 C.

FRANK J. SOWA.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 2,390,941 Jones Dec. 11, 1945 2,544,141 Donleavy Mar. 6, 1951 

1. AN HERBICIDAL COMPOSITION COMPRISING AS ACTIVE INGREDIENTS FROM 1 TO 50 PARTS BY WEIGHT OF AN AMMONIA-BORON FLUORIDE COMPOUND SELECTED FROM THE GROUP CONSISTING OF MONOAMMINO BORON TRIFLUORIDE AND AMMONIUM FLUOBORATE AND FROM 1 TO 30 PARTS BY WEIGHT OF A CHLORO PHENOXY ACETIC ACID COMPOUND SELECTED FROM THE GROUP CONSISTING OF THE AMMONIUM AND AMINE SALTS AND THE ESTERS OF 2,4-DICHLORO PHENOXY ACETIC ACID AND 2,4,5-TRICHLORO PHENOXY ACETIC ACID TOGETHER WITH A WETTING AGENT WHICH IS COMPATIBLE IN AQUEOUS SOLUTION WITH SAID INGREDIENTS. 